dm: Drop the block_dev_desc_t typedef

Use 'struct' instead of a typdef. Also since 'struct block_dev_desc' is long
and causes 80-column violations, rename it to struct blk_desc.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
diff --git a/cmd/reiser.c b/cmd/reiser.c
index 8871564..1cca5eb 100644
--- a/cmd/reiser.c
+++ b/cmd/reiser.c
@@ -34,7 +34,7 @@
 {
 	char *filename = "/";
 	int dev, part;
-	block_dev_desc_t *dev_desc=NULL;
+	struct blk_desc *dev_desc = NULL;
 	disk_partition_t info;
 
 	if (argc < 3)
@@ -82,7 +82,7 @@
 	int dev, part;
 	ulong addr = 0, filelen;
 	disk_partition_t info;
-	block_dev_desc_t *dev_desc = NULL;
+	struct blk_desc *dev_desc = NULL;
 	unsigned long count;
 	char *addr_str;